Improvement in cooling car-wheels



'ilNrTnnf STATES PATENT Ormea.

R. POOLE, OF BALTIMORE, MARYLAND, ASSIGNOR TO HIMSELF AND GERMAN H. HUNT, OF SAME PLACE.

IMPROVEMENT INCOOLING CAR-WHEELS.

Specification forming part of Letters Patent No. 20,924, dated July 13, 1858.

To aZZ whom, it may concern:

Be it known that I, ROBERT POOLE, of Baltimore, :in the county of Baltimore and State of Maryland, have 4invented or discovered a new and useful Improvement in the Process of Cooling Car-Wheels; and I do hereby declare the following to be a full, clear, and exact description thereof, and of what distinguishes it from all other inventions or discoveries for a similar purpose, reference being had to the accompanying drawings, which illustrate the invention, and in which drawings* Figure l represents a disk-wheel with spokes. Fig. 2 represents a central section through the same. Fig. 3 represents aspoke-wheel alone, and Fig. 4 av central section through it.

These two kinds of wheels will sufficiently illustrate my invention; butIby no means conne myself to any special form of wheel so long as my process is followed in making, or, rather,in casting and cooling, it,for many forms of wheels may be produced without departing 'from what I deem to be the characteristics of my invention, as will be hereinafter stated. All wheels, unless regularly cooled, exist with a strain, caused by unequal contraction. Some endeavor to overcome this strain by a subsequent'annealing process, and some by adopting curved shapes in the web of the wheel, to give or spring to the strain. These are both objectionable methods, the first softening the chill and injuring the strength of the wheel by endeavoring to remove in a degree a strain already in it. The second produces a wheel having the strain in it, but the shape arranged with the idea of making it less apparent, but so far as strength is concerned, compared with the weight, is an injudicious application of metal or material.

I aim to make a wheel which shall be regularly cooled in all its parts, and thus be produced free from strain withinit'self-a matter which heretofore required to be overcome by annealing or the adoption of curved shapes in the web of the wheel, which detract in my judgment from the strength and quality of the wheel. I do not therefore resort to either annealing or curving or corrugating the web of the wheel, by which means I avoid the inj urious effects of the rst process, and am able to make a better disposition of the material than by the second arrangement, Vplacing the metal more in a direct line with the thrust or strain on the wheel, and thus having greater strength in proportion to the weight of material than when the web is curved or corrugated.

My process might be called one for cooling car-wheels after they are cast, and without removing them from'the' fiask in which they are cast; but this process of cooling prevents the strain which it is believed exists in all wheels,

though better concealed in some than in others, Y

and therefore involves in its product or result other material features. I prevent the strain, and therefore do not have to resort to a remedy for an evil which I do not produce. My process also admits of the construction of wheels which need not have curved or corrugated webs, and thus I can better and more economically dispose of the material in the wheehmaking every part of it capable of sustaining its due portion of the strain or weight that comes upon them, not having to make any disposition of it to compensate for the spring or yield, or what is termed the shrinkage 7 of the metal,as in the former methods of casting, aunealing, and cooling.v I make no provision for contraction of the metal by curving the web of the wheel, because I do not allow that kind of contraction to take place. I prevent the evil, and do not therefore have to resort to a remedy against it; and although my invention may be termed aprocess for cooling earwheels in the flasks in which they are cast, yet this cooling effects three important elements in the wheel, viz: First, it is without strain within itself; second, it is not annealed andthe chill consequently not impaired 5 third, the material in the wheel can be disposed to resist the weight that it is subject `to alone, and not for the shrinkage or contraction that they encounter in the former modes of making carwheels, and thus a lighter wheel can be made stronger than when curved webs are used, and where the strain runs across the corrugations.

My invention,therefore, consists in a process for regularly or equably cooling car-wheels in the flasks in which they are cast, so that all strain within itself shall be avoided, annealing dispensed with, and the web of the Wheel need not be corrugated or curved to compensate for unequal contraction.

To enable others skilled in the art to make and use vmy process, I will proceed to describe 2' einem the same with reference to the drawings so far as they are applicable in illustrating a process.

The ilasks which I prefer to use may be constructed like those patented to myself and G; H. Hunt on the 20th April, 1858, to which reference is hereby made, they being made in section, so that such portions of them may be removed or replaced as will allow certain portions of the wheel to cool faster than other portions, as will be hereinafter explained, so that it shall be regularly cooled in all its parts, some requiring more exposure than other parts to make the cooling cquablc at all times and in all places.

In the preparation of the flasks in the molding of the wheel, or the pouring ofthe molten n1et-al,I claim nothing. They may all be done as heretofore. My process commences after these operations have been completed, viz: After the wheel is cast, and as soon thereafter as the iron becomes set,77 the outer section of the cope is removed, and the chill77 is taken out ol' the flask and the cope replaced. The central part of the flask should be lined with some non-conducting material, (as in the patent heretofore referred to,) and the molding-sand remaining in the outerseetion of the cope, the wheel is eiiectually protected from the action of the external air, and is left free to cool equally in all its parts; but as the tendency to contraction and cooling is greater or more rapid at the circumference than toward the center of the wheel, itbecoines requisite at a proper time to provide for a more rapid cooling at the central parts. This I eit'ect by admitting air to the central parts, while theriin is protected by the surrounding non-conduct ing material. This is all done before the wheel becomes rigid, and the cooling process may with little practice be so managed as to insure uniform cooling and produce a wheel free from strain. The wheels after remaining in the ilasks a proper time are then placed in a pit, and remain there until cold. By this process I can produce a car-wheel such as seen at A in Figs. 1 and 2 or as B (shown in Figs. 3 and 4) which shall be free from strain, unannealed, and without a curve or corrugation in its web; or, in other words, I make a solid wheel without eorrugations, without annealing, and without any strain within itself-a thingherctofore deemedimpossible or impractieablc. The process may therefore be said to consist in 'removing the outer section of the cope, taking out the chill and replacing the cope, and allowing thewheel to remain in the ilask until a suitable time for putting it into into a pit, where it remains until. cold, as hereinabove described.

Having thus fully described the nature of my invention or discover v,what I claim therein as new, and desire to secure by Letters Pat cnt, is-

The within-described process of regularly cooling car-wheels, whereby all .strain Within the wheel is avoided, the chill uninj ured, and the web of the wheel is without curve or corrugation, substantially as described.

ROBT. POOLE.

TWitnesses:

JOHN S. HARPER, JOHN A. TYLER. 

